#include <stdio.h>
#include <stdbool.h>

#define TIMESCALE 60

int timeChange(int time) {
    int result = (time / 100) * TIMESCALE + (time % 100);
    return result;
}

int main() {
    int time;

    while (true) {
        printf("请输入开始时间 \n  PS：输入格式：1120   11点20分\n");
        scanf("%d", &time);
        int _time = timeChange(time);
        printf("请输入结束时间\n");
        scanf("%d", &time);
        time = timeChange(time);

        time = time - _time;

        if (time >= 0) {
            printf("时间差为：%d小时%d分钟\n", time / TIMESCALE, time % TIMESCALE);
            return 0;
        } else {
            printf("错误：结束时间大于开始时间\n");
        }
    }

}
